"I will never judge somebody and won't put my finger in someone's face. I just want people to be aware of the fact that you cannot walk into an abortion clinic one day and think that you're going to walk out and be the same person as when you walked in," she said.

Duffy is on one side of the passionate debate. Yasemin Ayarci is on the other.

"What we want to do is lower the rates of abortions. We want to join them in that fight. But we want to do it through more rational means with sex education and birth control access," said Ayarci.

This is the 40th anniversary of the Supreme Court decision that legalized abortion - known as Roe vs. Wade. Each year, tens of thousands make a "right to life" march to the high court.

Young Americans, like Kristan Hawkins, were born after the landmark decision.

“This generation, my generation, those of us who survived legal abortion, we’re a pro-life generation,” said Hawkins.

But the pro-life arguments run counter to a recent NBC-Wall Street Journal survey that shows 70 percent of Americans do not want the right to abortion overturned.

Father Frank Pavone leads the anti-abortion group Priests for Life.

“We have very powerful forces in America to shape public opinion and defend the abortion industry - Planned Parenthood, for example - very well-funded organizations, much of the funding coming from the government itself, that have created public perception that this is a responsible activity,” he said.

Marcia Greenberger is an attorney specializing in women's law. She said the issue is political.

“Nothing is ever secure forever, and because a determined minority and pretty quiet complacent majority, there have been people put on our federal courts who are bound and determined to limit, or even overturn, Roe v. Wade," said Greenberger.

Some of those judges are here at the Supreme Court. But there is no immediate plan to review Roe vs. Wade.